Effect Of Sterilization Research Articles

Effect of solution plasma process on microorganism sterilization, physicochemical properties and nutrients of milk

Solution plasma process (SPP) was used for sterilizing Staphylococcus aureus (S. aureus) in raw milk (RM). The sterilization efficacy analysis and kinetics analysis showed bacterial concentration and the distance between electrodes were negatively correlated with the sterilization effect, while discharge voltage was positive. The better sterilization effect was achieved at 4 kV. The electrochemical indices analysis indicated that pH value of RM had no changed. The DO content decreased. The conductivity increased with the increasing discharge voltage. The nutrient content analysis revealed that the content of acidity, lactose, fat, and protein decreased. RM after SPP treatment exhibited higher values of sourness and slightly lower values of astringency than the control. The higher discharge voltage and narrower distance between electrodes presented the stronger effect. The structural characterization of CMs and MFGs was carried out using a laser particle sizer, FTIR, 1H NMR, XRD, and AFM. The results showed that the main chemical structure of CMs was unchanged basically. The SPP with the narrower distance between electrodes and lower discharge voltage significantly reduced the size and aggregation of MFGs at the molecular level. At 4 kV/2 mm, the particle sizes of CMs and MFGs were reduced from 238 nm and 523 nm to 224 nm and 302 nm, respectively. The average diameter of MFGs was reduced from 45 nm to 18 nm. Therefore, SPP is a potential method in the milk industry and provides a new idea for the preservation and processing of beverage.

Effect of hot air-assisted radio frequency rotation heating system on improving heating uniformity of dried black fungus (Auricularia auricula)

A large-capacity radio frequency (RF) rotation heating system was employed in this study to heat dried black fungus, and hot air was used for assistance treatment. The effects of electrode gap, rotation rate and hot air on the uniformity of RF heating of dried black fungus were explored. The optimal heating process parameters were obtained, and the sterilization effect was validated. The results showed that the rotation system could significantly enhance the RF heating uniformity of black fungus (P > 0.05). The optimal heating process for heating a large-capacity (480 g) black fungus was to utilize RF heating assisted by 70 °C hot air with an electrode gap of 175 mm and a rotation rate of 60 rpm, followed by 30 min of heat preservation at 70 °C hot air with a rotation rate of 40 rpm. After the entire sterilization treatment, the heating uniformity index λ of black fungus was reduced to 0.027 ± 0.004, the total plate count decreased by 3 log CFU/g, and the moisture content dropped to below 13 %. The ideal RF heating uniformity and sterilization effect of black fungus were obtained in this study through the simultaneous use of hot air and rotation, providing a theoretical foundation for the application of RF technology in the processing of black fungus.

Post sterilization of intraoral scan body and the effect it has on the axes and distances between three adjacent implants: in-vitro study

BackgroundThe purpose of this pilot in-vitro study was to assess the effect of sterilization on the intra-implant axis, inter-implant axis, intra-implant distance and inter-implant distance of three implants in a straight line by using laboratory scanner (LBS) versus intra-oral scanner (IOS) with intra-oral scan bodies (ISB). Methods: A printed 3D model with three internal hex analogs in the positions 15#,16#,17# was used. Zirkonzhan (ZZ) intra-oral scan body (ISB), two-piece titanium was used. The ZZ ISBs were scanned by 7 Series dental wings (LBS) and 30 times by Primescan (IOS) pre sterilization and 30 times post sterilization. For each scan (pre and post) stereolithography (STL) file was created and a comparison between all the scans pre sterilization and post sterilization were superimposed on the laboratory scan by using a 3D analyzing software. A Kolmogorov-Smirnov test performed followed by Wilcoxon Signed Ranks tests. (p < 0.05) Results: Post sterilization of the ZZ ISB, the mean errors were significantly increased for the inter-implant distances (p < 0.0005), intra-implant distances 1,2,3 (p < 0.0005), intra-implant axis 1,3 (p < 0.0005) and inter-implant axes 13,23 (p < 0.05). In contrast, the mean errors for intra-implant axis 2 (p < 0.0005) and inter-implant axis 12 (p < 0.0005) were significantly reduced. Conclusions: ZZ ISB showed changes in all four parameters after sterilization. The middle ISB had the largest changes in mean error regarding all four parameters. Sterilization process may affect the three-dimensional (3D) structure of the ZZ ISB after three cycles. There is a lack in the literature in this field and there is a need for further studies to explore the effect of sterilization (multiple cycles) on different ISBs and for creating an approved guidelines regarding the amount of sterilization for each ISB in the industry.

Enhancement of pork marinating efficiency through pulsed electric field pretreatment: Integration of parameter optimization, kinetic modeling and quality characteristics

Marination is an important part of meat processing, the disadvantage is that the process of marinating is slow and prone to losing nutrients. In this study, pork tenderloins were pretreated with pulsed electric field (PEF) before being immersed in the marinade at 4 °C. The aim was to investigate the effect of PEF pretreatment (PEFP) on the marination process, specifically mass transfer and the quality of the pork. Additionally, the response surface method (RSM) was employed to explore the optimal conditions for PEFP. Results showed that under the best condition (2 kV/cm, 141.2 Hz and 2.3% duty cycle), the NaCl content of pork cured for 6 h reached 3.31%, which could effectively shorten the marinating time of pork (up to 40%). After marinating for 6 h with PEFP, the weight, moisture, and salt changes increased significantly. The effective diffusion coefficient (De) was raised to 1.71 × 10−10 (PEFP) from 1.36 × 10−10 (control) and the kinetic model of mass transfer over time has good linear correlation. The scanning electron microscopy (SEM) results indicate that PEFP altered the muscle fibre structure of pork to some extent, resulting in loosely arranged muscle fibre bundles. The total bacterial colony count results showed that PEFP had a good sterilization effect on microorganisms in pork. Furthermore, PEFP does not alter the colour or pH of marinated pork while improving its tenderness. These results showed that PEFP could effectively promote salt diffusion to shorten marinating time and improve meat tenderness.

Amine plasma polymers deposited on porous hydroxyapatite artificial bone with bipolar pulsed discharges

A recent in vivo study [Kodama et al., Sci. Rep. 11, 1 (2021)] showed that porous artificial bones coated with amine-containing polymers deposited by plasma-enhanced chemical vapor deposition (PECVD) significantly enhanced bone regeneration. This article reports the chemical and physical properties of amine plasma polymers (PPs) formed under the same deposition conditions, including the film stability for up to two months, the effects of sterilization on the chemical compositions of the films, and the penetration of amine PPs into the inner surfaces of interconnected microscopic pores of the amine PP-coated porous artificial bone. It was found that, immediately after the plasma polymerization process, approximately 20% of nitrogen atoms on the surface of the deposited amine PP formed primary amines. However, the value decreased to approximately 5% over one month if the sample was exposed to ambient air. The relative concentration of primary amines also decreased to a similar value after the sample was sterilized by autoclaving or ethylene oxide gas. Molecular dynamics simulations were used to examine possible formation mechanisms of nitriles in deposit films under the PECVD conditions and found that ion impact can significantly reduce the nitrile content.

Innovative plasma treatment of orange juice to improve bioactive concentration: The effects of various parameters using response surface analysis.

Orange juice is a highly nutritious beverage. Traditional pasteurization methods cause nutrient loss and taste changes. Plasma treatment (PT) is an emerging method with a high sterilization rate. This study investigated the effects of corona discharge plasma on the sterilization of orange juice by changes in color difference, total phenol content, and pH value. Single-factor experiments revealed that higher voltage (40kV) and longer sterilization time (25min) had better sterilization effects. Response surface analysis indicated that frequency had the greatest impact on sterilization rates, and the optimal sterilization conditions were a voltage of 44.75kV, a frequency of 9.46kHz, and a sterilization time of 25min. Under these conditions, the sterilization rate reached 97.9%, meeting the national standard of 104 colony-forming units/mL (GB7101-2022). Compared to untreated juices, the color difference value was 16.32, the pH value decreased by 0.12, and the total phenol content increased by 0.669mg/mL. However, the evaporation of water plays an important role in increasing the total phenol co. Moreover, the comparative analysis showed that PT was comparable to pasteurization in terms of sterilization effects, flavor preservation, and the concentration of bioactive components. This study provides a theoretical basis for industrial applications of PT.

High-strength tile production from yellow clay with high silicon dioxide content and its reflection in ultraviolet and visible regions

Presently, there is an increasing global demand for high-quality raw materials in tile production owing to rapid urbanization. In addition, the issues of insufficient reserves and low-quality clays are resolved by exploring the potential of environmentally friendly Bilecik yellow clay with high SiO2 content. In this study, the feasibility of producing high-strength earthen tiles from yellow clay, which has a higher SiO2 content than that of commercially used clays, is investigated. X-ray diffraction, field-emission scanning electron microscopy, and X-ray fluorescence spectroscopy are employed to analyze yellow clay. The tiles are produced in the Hatipoglu Günes Tile and Brick Industry Inc. factories. Galette tiles are obtained using a vacuum press device. Then, the galette tiles are fired at temperatures of 900, 950, and 1000 °C in an electric and Hoffman furnace. The tile fired at 1000 °C exhibits the highest transformed flexural strength (305.371 kg/cm2), which is 2.55 times higher than that specified in the TS EN 1304:2016 standard (Turkish standard-European norm). In addition, reflectance measurements are performed in ultraviolet and visible regions through UV–VIS and Fourier-transform infrared spectroscopy; the results confirmed that the galette tiles are reflected in the UV-C region. Therefore, it can be concluded that galette tiles exhibit sterilization and disinfectant effects under appropriate conditions. The usability of yellow clay with high SiO2 content in industry, the availability of high-strength products, and its production stages will create an important database for literature.

A Clean and Health-Care-Focused Way to Reduce Indoor Airborne Bacteria in Calf House with Long-Wave Ultraviolet.

Long-term exposure to a relatively high concentration of airborne bacteria emitted from intensive livestock houses could potentially threaten the health and welfare of animals and workers. There is a dual effect of air sterilization and promotion of vitamin D synthesis for the specific bands of ultraviolet light. This study investigated the potential use of A-band ultraviolet (UVA) tubes as a clean and safe way of reducing airborne bacteria and improving calf health. The composition and emission characteristics of airborne bacteria were investigated and used to determine the correct operating regime of UVA tubes in calf houses. Intermittent exceedances of indoor airborne bacteria were observed in closed calf houses. The measured emission intensity of airborne bacteria was 1.13 ± 0.09 × 107 CFU h-1 per calf. Proteobacteria were the dominant microbial species in the air inside and outside calf houses. After UVA radiation, the indoor culturable airborne bacteria decreased in all particle size ranges of the Anderson sampler, and it showed the highest reduction rate in the size range of 3.3-4.7 μm. The results of this study would enrich the knowledge of the source characteristics of the airborne bacteria in intensive livestock farming and contribute to the environmental control of cattle in intensive livestock production.

Effect of power supply parameters on discharge characteristics and sterilization efficiency of magnetically driven rotating gliding arc

Plasma sterilization is a new generation of high-tech sterilization method that is fast, safe, and pollution free. It is widely used in medical, food, and environmental protection fields. Home air sterilization is an emerging field of plasma application, which puts higher requirements on the miniaturization, operational stability, and operating cost of plasma device. In this study, a novel magnetically driven rotating gliding arc (MDRGA) discharge device was used to sterilize Lactobacillus fermentation. Compared with the traditional gas-driven gliding arc, this device has a simple structure and a more stable gliding arc. Simulation using COMSOL Multiphysics showed that adding permanent magnets can form a stable magnetic field, which is conducive to the formation of gliding arcs. Experiments on the discharge performance, ozone concentration, and sterilization effect were conducted using different power supply parameters. The results revealed that the MDRGA process can be divided into three stages: starting, gliding, and extinguishing. Appropriate voltage was the key factor for stable arc gliding, and both high and low voltages were not conducive to stable arc gliding and ozone production. In this experimental setup, the sterilization effect was the best at 6.6 kV. A high modulation duty ratio was beneficial for achieving stable arc gliding. However, when the duty ratio exceeded a certain value, the improvement in the sterilization effect was slow. Therefore, considering the sterilization effect and energy factors comprehensively, we chose 80% as the optimal modulation duty ratio for this experimental device.

Design of an intelligent Near-Infrared responsive antibacterial Nano-Platform based on MoS2/Cu3Mo2O9

In this era of high drug resistance, there is an urgent need for novel antimicrobial agents and strategies to achieve smarter sterilization effects. However, developing an environmentally friendly, controllable, and self-cleaning smart antimicrobial material remains a formidable challenge. In this work, a smart antimicrobial nanoplatform composed of Cu3Mo2O9 and MoS2 has been successfully designed and synthesized. The computational findings reveal that, owing to the interfacial coupling between the two substances at the solid junction, this architecture can effectively absorb near-infrared light, significantly reduce migration resistance, and improve carrier separation efficiency. Empirical observations demonstrate that with a sample concentration of 100 μg/mL, under near-infrared (NIR) laser irradiation, the microenvironmental temperature proximal to the bacteria can be swiftly elevated from 28.6 °C to in excess of 50 °C within a mere 6 min. The overall photothermal conversion efficiency is 32.6 %, and it exhibits an active oxygen level nearly 5 times higher than that of Cu3Mo2O9. Furthermore, the permeability of the cell membrane was greatly improved with the increased temperature, which is beneficial for the generated reactive oxygen species (ROS) entering the bacterial cells. After synergistic antimicrobial treatment, the antibacterial rate against Escherichia coli can reach over 99 %. More importantly, this nano-platform features a unique ’activation’ mechanism that uses NIR as an ’activation switch’ to selectively toggle between ’passive defense,’ ’secondary sterilization,’ and ’active attack’ antibacterial modes as needed. Upon interaction with aqueous environments, its reusability and favorable biocompatibility with terrestrial and aquatic life promise to facilitate the intelligent eradication of deleterious microorganisms in aquatic systems via the diurnal cycle of sunrise and sunset. This is highly significant for the ongoing management and maintenance of public resources such as amusement parks, artificial fish ponds, and urban water features.

Improving detached tiller culture for doubled haploid production in wheat (T. aestivum L.) by post‐pollination fungicides application and UV radiation treatment

AbstractThis work aims at improving the proven protocol for doubled haploid production in wheat. This procedure has some deficits, for example, microbial infection of ears as well as of the nutrient culture medium. In the present study, the potential effect of sterilization by detached tiller culture fungicides of ears as well as of nutrient medium to control microbial infection, and its effect on the formation of caryopses and embryos (CFF, EFF) was studied. In a further experiment, the UV‐light was used as physical sterilant for the nutrient medium. All of the fungicides and their concentrations studied were found to be effective to control infection on ears except the concentration 0.05% tilt. 0.1% tilt gave the highest CFF (79.5%) followed by 0.1% Bayleton (78.0%). The lowest CFF was recorded in control treatment (48.8%). Among Bavistin treatments, the 0.2% Bavistin gave maximum CFF (68.5%) as well as EFF (29.1%) followed by 0.1% Bavistin (64.9%, 23.7%). The higher concentration of tilt (0.2%) showed detrimental effects on EFF (17.5%). Bavistin in tiller culture nutrient medium reduced infection in medium and was shown to improve CFF and EFF (67.4%, 29.8%).

Magnetic bio-based Fe3O4@urushiol-Fe polymeric nanoparticles for efficient photothermal sterilization

Many advantages of photothermal sterilization make it very promising in the field of sterilization. Biomass micro-nanoparticles with photothermal properties are considered worthy of development as photothermal sterilization materials. Urushiol, the main component of natural sap from lacquer tree, was applied to react with green-vitriol by the adjusted the concentrations of ferrous ion through the chemical synthesis method to prepare a novel magnetic composite nanoparticle with Fe3O4 as the central core wrapped by urushiol-Fe chelate polymer. Under 808 nm near-infrared irradiation (0.12 W cm−2), the Fe3O4@urushiol-Fe polymeric nanoparticles were rapidly heated up to a maximum temperature of 104.9 ℃, implying good photothermal conversion performance. The nanoparticles were applied for the effective inactivation of bacteria such as Escherichia coli and Staphylococcus aureus. The optimal dose and irradiation power for sterilization were 0.5 mg and 1 W cm−2, respectively. The composite nanoparticles exhibited good photothermal conversion stability even after multiple photothermal heating and photothermal sterilization. The biomass magnetic composite Fe3O4@urushiol-Fe polymer nanoparticles had the advantages of simple preparation, high efficiency of photothermal conversion, significant sterilization effect, and easy collection, which demonstrated a broad application prospect in the field of photothermal sterilization.

Flexible thin-layer plasma sterilizer based on polyimide and efficacy evaluation under bending deformation

Cold atmospheric pressure plasma is receiving attention in biomedical treatment for its non-thermal, dry-type, and high-efficiency disinfection effects on bacteria, fungi, and viruses, compared to typical sterilization methods, such as pasteurization, chemical solutions, and ultraviolet radiation. There are great demands of plasma decontamination on the surface of complex 3D objects, with the request of large coverage, convenience, and uniformity, which still remains a challenge for the current plasma devices. In this work, a flexible thin-layer plasma source for sterilization is developed based on a polyimide substrate, and its plasma generation process is characterized by experiment and simulation. The influences of bending deformation are studied and evaluated by electrical waveforms, heat radiation, and ozone production, of which the mechanisms are further explained. Results illustrate that the variation in electron impact ionization induced by different curvatures is the main cause leading to the change in microparticle production, thus affecting the macroscopic properties of plasmas. Activations of the plasma sterilizer for 30 and 120 s reduce both S. aureus and P. aeruginosa on the flat surface by around 2.5 and 5 log colony forming units (CFU). However, the plasma sterilization effect decreases with an extent of about 1 log CFU when treating the curved surface, while being regained after conforming the plasma sterilizer to the curved surface. This kind of plasma generator offers significant flexibility and efficacy, being promising for the treatment of objects with irregular surfaces in future plasma biomedicine and material processing.

Effects of physical sterilization on microbial safety, nutritional composition, and antioxidant activity of queen bee larva powder, a by-product of royal jelly production

Queen bee larvae (QBL), a by-product of royal jelly production, have nutritional value and confer health benefits. The commercialization of QBL is hindered because of the lack of evidence for its nutrition and safety parameters. Thus, this study was conducted to investigate the microbial dynamics, nutritional composition, and antioxidant activity of QBL, aiming to assess its potential as a food product. Lyophilized QBL powder samples were sterilized through gamma irradiation and high-pressure processing at varying doses and pressures. Gamma irradiation at 10 and 15 kGy effectively reduced the total aerobic count to 0, whereas high-pressure processing led to no significant reduction. Regarding the microbial profile of QBL, 16S rDNA gene sequencing unveiled five bacteria—Acinetobacter pittii, Bacillus thuringiensis, Enterococcus mundtii, Enterococcus faecalis, and Fructobacillus fructosus—but no major foodborne pathogens. Lactobacillus, Bombella, and Fructobacillus emerged as the predominant genera in QBL, with low abundances of Staphylococcus and Escherichia. Proximate composition analysis indicated no significant postirradiation changes in macronutrient contents; notably, protein was the predominant component (approximately 48.0%). Sugar and amino acid analyses revealed essential nutrients meeting human dietary requirements. Upon fatty acid analysis, palmitic and oleic acids emerged as predominant fatty acids. Gamma irradiation at 10 kGy exerted no significant effect on the nutritional composition or antioxidant activity of QBL. Our study provides valuable insights into the microbial safety and nutritional value of QBL, indicating its potential as a dietary protein source with favorable microbiota.

Preparation of TiO2 Nano-Flower Coating on Ti Substrates with Good Physical Sterilization Effect and Biocompatibility

Preparation of TiO2 Nano-Flower Coating on Ti Substrates with Good Physical Sterilization Effect and Biocompatibility

Effects of gamma(γ)-irradiation on the physicochemical properties and bioavailability of iron oxyhydroxides coprecipitated with varying concentrations of Na-alginate

This study investigated the impacts of γ-radiation at a final dose of 25 kGy on the physicochemical properties of a range of wet iron oxyhydroxides (2-line ferrihydrite, lepidocrocite, and goethite) synthesized in the presence of varying concentrations of the polysaccharide Na-alginate (starting solutions containing C/Fe ratios of 0, 0.5, 1.0, and 1.5). The degree of impact to the minerals was examined by chemical extractions, and various analytical techniques including XRD, FTIR-ATR, Mössbauer spectroscopy, and N2 adsorption-desorption isotherms, as well as by assessing their bioavailability towards the model Fe(III) reducing bacteria Shewanella putrefaciens CN32. Across all the coprecipitates studied, it was found that γ-irradiation led to a substantial dissolution of Fe and the concomitant release of Fe(II) and alginate into solution. Despite this observation, the bulk mineralogy and crystallinity of the studied iron oxyhydroxides, as determined by XRD and FTIR-ATR, did not appear to change. However, analyses via Mössbauer spectroscopy (77 and 5 K) revealed that the crystallinity of the 2-line ferrihydrites increased post-irradiation. Moreover, among the minerals studied, the specific surface area and porosity decreased for only the post-irradiated 2-line ferrihydrite coprecipitates with a C/Fe ratio of 0.5 or 1.0. The bioreduction rates of the studied minerals and their irradiated counterparts did not significantly differ, whereas the extent of bioreduction of post-irradiated 2-line ferrihydrite coprecipitates (C/Fe 0.5, 1.0, and 1.5) exhibited a significant increase of up to 28%. In contrast, the extent of Fe reduction for select post-irradiated lepidocrocite (C/Fe 0.5) and goethite (C/Fe 1.5) coprecipitates was slightly higher than determined for their corresponding native controls. The observed differences in bioavailability between the native and irradiated coprecipitates were attributed to irradiation induced alteration of particle aggregation and coagulation as determined by particle size analyses and visual observations. In summary, the findings suggest that even a low total dose of 25 kGy, γ-radiation can lead to significant physicochemical changes in coprecipitates with relatively low organic matter content. Therefore, future research designed to investigate organic matter-Fe composite systems in natural samples should be cognizant of the potential effects of sterilization through γ-irradiation. These effects could potentially result in inaccurate over- or under- estimations of the bioavailability of Fe or organic matter, as well as the possible adsorption capacity of organic matter-Fe coprecipitates for contaminants.

Insight into the mechanism of high hydrostatic pressure effect on inhibitory efficiency of three natural inhibitors on polyphenol oxidase

The development of natural inhibitors of polyphenol oxidase (PPO) is crucial in the prevention of enzymatic browning in fresh foods. However, few studies have focused on the effect of subsequent sterilization on their inhibition efficiency. This study investigated the influence and mechanism of high hydrostatic pressure (HHP) on the inhibition of PPO by epigallocatechin gallate (EGCG), cyanidin-3-O-glucoside (C3G), and ferulic acid. Results showed that under the conditions of 550 MPa/30 min, the activity of EGCG-PPO decreased to 55.92%, C3G-PPO decreased to 81.80%, whereas the activity of FA-PPO remained stable. Spectroscopic experiments displayed that HHP intensified the secondary structure transformation and fluorescence quenching of PPO. Molecular dynamics simulations revealed that at 550 MPa, the surface interaction between PPO with EGCG or C3G increased, potentially leading to a reduction in their activity. In contrast, FA-PPO demonstrated conformational stability. This study can provide a reference for the future industrial application of natural inhibitors.

Effect of Autoclave Sterilization on the Number of Uses and Resistance to Cyclic Fatigue of WaveOne Gold and Four Replica-Like Endodontic Instruments.

This study aimed to evaluate the effect of autoclave sterilization on the integrity and instruments' fracture number after multiple uses and cyclic fatigue of the original WaveOne Gold (Dentsply Sirona Endodontics) compared to four replica-like instruments (TF4-Gold, Roll-Wave-Gold, W-File, and Micro-Gold). The instruments were analyzed by scanning electron microscope (SEM) before being used in root canal instrumentation (baseline). One hundred and fifty human molars, freshly extracted for orthodontic reasons or periodontal disease and with severe curvature (between 30° and 60°), were used. Fifty teeth were instrumented with 10 instruments from each group and were evaluated for integrity. After sterilization in an autoclave, the instruments were analyzed by SEM. This procedure was repeated twice more, totaling three rounds of instrumentation, sterilization, and SEM analysis. Ten unused instruments from each group were evaluated for resistance to cyclic fatigue in a static test using a motor and a device simulating a canal with a 60° curvature angle. The instruments were driven by the motor until separation, visually verified, and the time measured in seconds. Data were analyzed by Chi-square, one-way ANOVA, and Tukey analysis, considering a significance level of 5%. It was found that there was no statistically significant difference between the groups tested in the effect of sterilization on the number of uses. The SEM analysis showed distortions in the instruments after the 3rd use. There was a statistically significant difference in the cyclic fatigue test between the results of WaveOne Gold, TF4 Gold, and Roll Wave Gold compared to W File and Micro Gold (P < 0.0001) and a statistically significant difference between the W File and Micro Gold groups (P < 0.0001). In conclusion, this study affirmed that WaveOne Gold, TF4-Gold, and Roll-Wave-Gold instruments exhibit comparable cyclic fatigue resistance. Besides, all examined instruments can be reliably employed for up to two cases.

Effects of sterilization and disinfection methods on digitally designed surgical implant guide accuracy: An in vitro study.

Surgical guides are commonly used to assist with dental implant placement. This study investigated the effects of five sterilization and disinfection methods on the accuracy of implant guides. Thirty surgical guides (five in each group) were designed and printed (with digital light processing technology) using different sterilization or disinfection methods categorized into six groups: hydrogen peroxide sterilization (group one); glutaraldehyde sterilization (group two); autoclaving (group three); plasma sterilization (group four); iodophor disinfection (group five); and blank group (group six). Verification was determined using three methods: distance and angle between the cross-shaped marks, deformation after superimposing the guides, and displacement and axial changes in the virtual implant. After disinfection and sterilization, the guides in the autoclaving and iodophor groups showed a more pronounced color change and the guidein the autoclaving group had visible cracks. More significant changes were observed in the H2O2, glutaraldehyde, autoclaving, and iodophor groups regarding deformation after superimposing the guides and the distance and angle between the cross-shaped marks. The average labial deformation values (mm) of the first through fifth groups of guides were 0.283, 0.172, 0.289, 0.153, and 0.188, respectively. All groups were statistically different from the blank group for displacement and axial changes of the virtual implant (p < 0.05). The sizes of almost all surgical guides changed after sterilization and disinfection treatments, with between-group differences. Plasma sterilization was more suitable for surgical guide sterilization because of the smaller deformations after treatment.

Effect of simulated clinical use and sterilization on the cyclic fatigue resistance of nickel titanium files.

Assess the effect of simulated clinical use and sterilization on the cyclic fatigue resistance of Race Evo and Tia Tornado Blue nickel titanium (NiTi) files. For this study, a total of sixty-four NiTi files were selected, with thirty-two files each from two different manufacturers. Files from each manufacturer were subdivided into four subgroups (n=8) based on the test parameters. The control groups included files that were neither used nor sterilized. Files from the test groups were used to prepare the root canals of extracted mandibular premolars and then sterilized. This procedure was repeated once, twice, or thrice, depending on the test group. All files were then subjected to a cyclic fatigue test. Data was statistically analyzed using the Kruskal-Wallis and Mann-Whitney U tests. No significant difference was observed in the number of cycles to failure (NCF) among the subgroups for both types of files (P=0.869 for Tia Tornado Blue, P=0.626 for Race Evo). Tia Tornado Blue files displayed significantly higher NCF values in the control (P=0.021), once (P=0.027), and thrice (P=0.031) usage groups when compared to Race Evo files. Repeated clinical use and sterilization for up to three cycles did not affect the cyclic fatigue resistance of Race Evo and Tia Tornado Blue files.